Electrical deployment control system for underwater ordnance

ABSTRACT

Control apparatus for separating a mine casing from its anchor having a series of switches located in an explosive programmer which activates a main power source for the mine. The power source is serially connected to a normally open explosive switch in the explosive programmer, a hydrostatic pressure responsive switch, an electrically energizable explosive casing release, a tilt switch which is normally open whenever the mine is not vertically oriented, and a normally closed explosive switch also in the explosive programmer for sterilizing the system by opening after a predetermined time period.

United States Patent Noel Mar. 14, 1972 [54] ELECTRICAL DEPLOYMENT CONTROL SYSTEM FOR UNDERWATER ORDNANCE [72] inventor: Earl A. Noel, Deerwood, Md.

[73] Assignee: The United States of America as represented by the Secretary of the Navy [22] Filed: May 13, 1970 [21] Appl. No.: 36,725

[52] US. Cl ..l02/l3, 102/16, 102/702 [51] Int. Cl ..F42b 22/00 [58] Field of Search ..l02/7, 10, 13,14, 16, 22,

[56] References Cited UNITED STATES PATENTS 2,980,020 4/1961 Smith ..102/70.2

3,337,255 8/1967 Nicolofi 102/14 3,420,176 1/1969 Pope 102/702 3,570,404 3/1971 Pope 102/702 Primary ExaminerVerlin R. Pendegrass Attorney-R. S. Sciascia and J. O. Tresansky [57] ABSTRACT Control apparatus for separating a mine casing from its anchor having a series of switches located in an explosive programmer which activates a main power source for the mine. The power source is serially connected to a normally open explosive switch in the explosive programmer, a hydrostatic pressure responsive switch, an electrically energizable explosive casing release, a tilt switch which is normally open whenever the mine is not vertically oriented, and a normally closed explosive switch also in the explosive programmer for sterilizing the system by opening after a predetermined time period.

5 Claims, 5 Drawing Figures Patented March 14, 1972 2 Sheets-Sheet 1 I l RESPONSIVE L "fi EXPLOSIVE ACTUATOR BATTERY 48 PROGRAMMER L I6 46 /0 F IG. 3

/60 m 40 j 62 E5 660 DEPTH N56 INVENTOR' CONTROLLER Earl A. Noel PAYOUT 58 BY '0 l POTENTIOMETER ATTO EY Patented March 1-4, 1912 3,648,611

2 Sheets-Sheet 2 FIG. 5.

ELECTRICAL DEPLOYMENT CONTROL SYSTEM FOR UNDERWATER ORDNANCE BACKGROUND OF THE INVENTION This invention generally relates to an underwater ordnance deployment control system and more particularly to a mine casing and anchor separation electrical control system.

Mines launched by conventional means such as submarine torpedo tubes are provided with a mine casing integrally connected to an anchor, the casing and the anchor being adapted to separate when the mine is at a predetermined safe distance from the launching vehicle. Up to the time of separation, the casing and anchor assembly has a negative buoyancy and, therefore, tends to sink. Upon separation, the anchor remains negatively buoyant and continues to descend in the water while the mine casing, now positively buoyant, tends to rise toward the surface. By virtue of a cable interconnecting the casing and the anchor, the casing can be moored at a predetermined depth by the anchor which lodges on the ocean floor.

In the past, problems have resulted from premature separation of the anchor from the mine casing. When such a premature separation occurs after the torpedo mine assembly has exited from a torpedo tube relatively minimal damage results, such damage being confined to improper positioning of the mine. More serious consequences result, however, when the mine casing anchor separation is effected while the mine is still in the torpedo tube. In circumstances such as these, not only is at least one torpedo tube rendered incapable of further use but a danger is constantly present of the mine exploding within the tube thereby destroying the launching submarine.

Safety features have been provided in some firing tubes whereby mine casing-anchor separation has been precluded until the mines have left the tube. Such provisions, however, do not prevent such mishaps as premature separation after the mine has left the tube as discussed hereinbefore. Further, these features have not proved entirely foolproof and occasional separations have continued to occur with the mine still in the launching tube.

A continuing need exists therefore for a mine control system which will ensure against separation of the mine casing from the anchor until certain predetermined conditions are SUMMARY OF THE INVENTION Accordingly, one object of the invention is to provide a new and improved system for effecting a safe separation of a mine casing from its anchor.

Another object of the invention is to provide an apparatus to effect a separation of a mine casing from its anchor at a specific predetermined depth.

Still another object of the present invention is to provide an apparatus to effect a separation of a mine casing from its anchor when the mine is in a specific predetermined orientation.

A further object of the instant invention is to provide apparatus which will effect separation of assembled bodies at a predetermined time after a predetermined depth is reached.

Briefly, in accordance with one embodiment of this invention, these and other objects are obtained by providing a separation control system having an electroresponsive programmer which upon being ignited by a hydrostatic pressure responsive electrical energy source sequentially operates a plurality of electrical switches in a predetermined time sequence. Operation of one of the programmer switches actuates a source of electrical energy for igniting an electroresponsive charge in a circuit for effecting severance of physical restrainers holding assembled the devices to be separated upon actuation of a hydrostatic pressure responsive switch, operation of a second one of the programmer switches and an assembly orientation responsive switch located within the circuit.

BRIEF DESCRIPTION OF THE DRAWING A more complete appreciation of the invention and many of the attendant advantages thereof will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawing wherein:

FIG. I is a perspective view of the explosive programmer utilized in mine separation control circuit;

FIG. 2 is a sectional view of the explosive programmer of FIG. I out along line 2-2;

FIG. 3 is a diagrammatic view of the actuating system for the explosive programmer;

FIG. 4 is a schematic view of the mine separating circuit; and

FIG. 5 is a pictorial illustration of the successive stages of mine casing-anchor separation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing wherein like reference characters designate identical or corresponding parts throughout the several views, and more particularly to FIGS. 1 and 2 thereof, an explosive programmer 10 is shown which includes a rectangular housing 12 having an internal electroresponsive explosive powder delay column 14 running the length thereof. Electrically conducting leads 16 are connected to a bridgewire l8 imbedded within one end of explosive column 14. The bridgewire l8 ignites the column when energized by a suitable source of electricity. The delay column 14 is packed with powder that burns at a precisely controlled rate.

Spaced along the length of one face of housing 12 are a plurality of cylindrical bores 20, 22, 24 and 26 which communicate with delay column 14 at right angles thereto at one end and are closed at the opposite end. Slidably positioned within each bore is a cylindrical piston 28 which initially is disposed substantially adjacent to the delay column 14 as shown by the cylinders positioned in bores 24 and 26. A small explosive charge 30 is provided in each bore at the intersection thereof with delay column 14. As the burning front 31 advances along the delay column 14 subsequent to ignition thereof by bridgewire 18, the front sequentially ignites each explosive charge 30 driving each piston 28 downward in its respective bore. As exemplified by pistons 28 in bores 20 and 22, all four pistons sequentially come to rest at the bottom of their respective bores to thereby either close or open a circuit formed by sets of electrical leads 32. When the conductive path is to be closed the lower portion of piston 28 is of a conductive material and completes the circuit by mutually contacting the ends of leads 32. In the case of opening a normally closed switch as seen in bore 26, piston 28 includes a knife edge 29 formed of non-conductive material which separates the two leads 32 which are in contact prior to the switch functioning. It is to be noted that in this manner four explosively actuated switches 34, 36, 38 and 40 are formed which may be actuated in a programmed predetermined sequence depending upon the burning rate of the delay column 14.

FIG. 3 schematically illustrates the manner in which the explosive programmer 10 is actuated. The actuation system 42 for the programmer includes a hydrostatic pressure responsive actuator 44 and a thermal battery 46. The pressure responsive actuator 44 may be any one of a number of conventional hydrostat devices such as of the diaphragm or piston type, which, when exposed to a predetermined hydrostatic pressure, releases a percussion pin, shown here diagramatically as 48. The actuator 44 is located in the mine anchor in a conventional manner whereby it is exposed to the ambient hydrostatic pressure. When the hydrostatic pressure reaches a certain value, percussion pin 48 is thrust forward and initiates a small explosive charge (not shown) in battery 46 thereby creating sufficient thermal energy to actuate the battery. Squib leads 16 from explosive programmer 10 are connected to thermal battery 46 and upon the battery actuation, voltage is applied across bridgewire 18 in the programmer l and the hereinbefore described controlled burning of the delay column is initiated.

Referring now to FIG. 4 wherein the mine separation circuit is shown just prior to activation of battery 46 by percussion pin 48, upon activation of battery 46. the explosive programmer parallel coupled through switch 34 therewith is initiated as discussed hereinbefore and the burning of the powder in delay column 14 is begun. After a predetermined short time interval switch 34 is explosively opened thereby removing the programmer from the circuit and preventing the dissipation of all of the energy in battery 46.

A main anchor battery assembly 50 is provided which includes a battery 52 and a electroresponsive explosive squib 54. Battery 52 may be one of many types of batteries that may be actuated by a small explosion such as a thermal battery. The burning front traversing delay column 14 reaches switch 36 after a predetermined amount of time and closes switch 36 as discussed hereinbefore. Switch 36 is serially connected to squib 54 and upon closure completes a circuit between thermal battery 46 and squib 54 thereby initiating the squib 54 and actuating main anchor battery 52. It is to be noted that this energization can be delayed by the appropriate selection of the time interval between the opening of switch 34 and the closing of switch 36.

After activation, battery 52 supplies electrical energy to various electroresponsive devices connected parallel thereto in the mine anchor such as a conventional depth controller 56 and cable payout potentiometer 58. Depth controller 56 and payout potentiometer 58 integral therewith comprise a servo system which regulates the rate of payout of the cable interconnecting the mine casing and assembly by measuring the depth of the anchor and comparing it to a reference figure representative of the desired rate of cable payout.

Connected in parallel to the devices discussed hereinabove is a mine separation circuit 60 which serially includes normally open switch 38, and normally closed switch 40 of programmer 10, a conventional mercury tilt switch 62, a normally open conventional hydrostatic responsive switch 64, an electroresponsive explosive charge 66 which functions as the mine separation actuator as will be described hereinafter, and a capacitor 68. Switch 64 may be of a conventional type including a pressure responsive piston or bellows which is actuated at a predetermined pressure. By the timed, sequential closing of the programmer switches a circuit path will be completed and the explosive charge 66 detonated.

Before the burning front in delay column 14 in explosive programmer 10 reaches switch 38, the mine normally will have descended to a depth where the pressure is sufficient to actuate hydrostatic responsive switch 64.

At some time subsequent to the closing of hydrostatic switch 64, switch 38 in explosive programmer 10 is closed in the manner discussed hereinbefore. The functioning of explosive switch 38 is timed to cause it to remain open until the mine is a safe distance from the launching platform. This timed closure further insures that the detonation of explosive charge 66 is not achieved until the mooring sequence, described hereinafter, is begun, even if the pressure responsive switch 64 closed prematurely.

Mercury tilt switch 62, which is connected serially to explosive switches 40 and 38, and hydro-switch 64 normally maintains the circuit open and prevents detonation of charge 66 in an unusual circumstance where the mine is not orienting itself into an appropriate vertical position. More specifically, tilt switch 62 remains open until the longitudinal axis of the mine assumes a desired angle, such for example as with the vertical. When the desired angle is reached tilt switch 62 closes and the circuit is complete whereupon the electroresponsive explosive charge 66 is initiated by the electrical energy of battery 52.

Upon the detonation of explosive charge 66 the bands 66a clamping together the mine casing and anchor are severed, as by a driven knife edge 66b effecting separation of the mine casing 74 from its anchor 72. It is to be particularly noted that the mine will not separate until a sufficient time for safe tube clearance is insured by the time closure of explosive switch 38, a sufficient depth is achieved as sensed by hydro-switch 64 and a predetermined orientation of the mine is effected as sensed by tilt switch 62. if the mine becomes caught in the launching tube, it is evident that the tilt switch 62 will remain open and thereby prevent the anchor-casing separation.

To prevent excessive drainage of energy from battery 52, a capacitor 68 is connected serially within the circuit. After the circuit is closed current will flow for a short time, allowing the actuation of explosive charge 66 until the capacitor 68 is fully charged, at which point current flow ceases and the circuit is effectively opened.

Normally closed, explosive switch 40 in the explosive programmer 10 is adapted to open after sufficient time has lapsed from actuation of battery 46 to allow the mine to moor. Failure of the mine to moor during this interval, is an indication of a potentially dangerous situation; i.e., the mine may have been caught in the extension of the torpedo tube. After final explosive switch 40 opens, the unmoored mine is essentially sterile. Complete sterilization is accomplished a short time later when energy in main anchor battery 52 is completely dissipated.

It is to be understood that after separation has been accomplished, battery 52 continues for a time to supply energy to the depth controller 56 and payout potentiometer 58 contained in the mine anchor.

A typical mooring sequence is illustrated in H6. 4. After reaching a predetermined depth after launching, a mine 70 will begin to descent clue to its negative buoyancy. When the mine orients itself to the desired angle relative to the vertical, mercury tilt switch 62 completes the separation circuit as hereinbefore described and the explosive charge 66 is fired thereby effecting the separation of anchor 72 from mine casing 74. Remaining negatively buoyant, anchor 72 continues to descend until it reaches the ocean floor as shown. Payout potentiometer 58 selectively releases cable 76 and mooring of the mine casing 74 which alone is positively buoyant is thereby achieved.

Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. lt is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described herein.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

I. An electrical control system for effecting separation of a normally interconnected mine casing and anchor comprising:

electroresponsive programmer means for sequentially operating a plurality of electrical switches in a predetermined time delay sequence upon ignition thereof;

normally unactuated first electrical energy source means connectable to said electroresponsive programmer means for effecting ignition of said electroresponsive programmer means in response to actuation thereof at a predetermined hydrostatic pressure;

normally unactuated second electrical energy source means actuable by said first electrical energy source means upon operation of a first one of said plurality of electrical switches;

a mine separation actuation circuit coupled to said second electrical energy source means, said circuit including, electroresponsive explosive means for effecting severance of the interconnection between the mine casing and anchor,

a normally open electrical switch actuable to be closed in response to a predetermined hydrostatic pressure,

a second one of said plurality of electrical switches operable to a closed position a predetermined time interval after operation of said first one of said plurality of switches, and

a normally interrupted electrical switch operable to be rendered continuous in response to a predetermined orientation of the mine casing thereby effecting initiation of said electroresponsive explosive means by said second electrical energy source means.

2. An electrical control system according to claim 1 wherein said mine separation actuation circuit includes a capacitor for limiting the flow of energy from said second electrical energy source means.

3. An electrical control system according to claim 1 wherein said mine separation actuation circuit includes a third one of said plurality of switches actuable to an open position a predetermined time after operation of said second one of said plurality of switches thereby to permanently render ineffective said mine separation actuation circuit.

4. An electrical control system according to claim 1 wherein a fourth one of said plurality of electrical switches is operable a predetermined time after ignition of said electroresponsive programmer means for interrupting the connection between said electroresponsive programmer means and said first elec trical energy source.

5. An electrical control system according to claim 1 wherein said electroresponsive programmer means includes an elongate explosive power train having a controlled burning rate and a plurality of piston means each being disposed at spaced positions along the length of said train and movable to effect operation of respective ones of said plurality of switches as the burning of said train reaches the respective position of each of said piston means. 

1. An electrical control system for effecting separation of a normally interconnected mine casing and anchor comprising: electroresponsive programmer means for sequentially operating a plurality of electrical switches in a predetermined time delay sequence upOn ignition thereof; normally unactuated first electrical energy source means connectable to said electroresponsive programmer means for effecting ignition of said electroresponsive programmer means in response to actuation thereof at a predetermined hydrostatic pressure; normally unactuated second electrical energy source means actuable by said first electrical energy source means upon operation of a first one of said plurality of electrical switches; a mine separation actuation circuit coupled to said second electrical energy source means, said circuit including, electroresponsive explosive means for effecting severance of the interconnection between the mine casing and anchor, a normally open electrical switch actuable to be closed in response to a predetermined hydrostatic pressure, a second one of said plurality of electrical switches operable to a closed position a predetermined time interval after operation of said first one of said plurality of switches, and a normally interrupted electrical switch operable to be rendered continuous in response to a predetermined orientation of the mine casing thereby effecting initiation of said electroresponsive explosive means by said second electrical energy source means.
 2. An electrical control system according to claim 1 wherein said mine separation actuation circuit includes a capacitor for limiting the flow of energy from said second electrical energy source means.
 3. An electrical control system according to claim 1 wherein said mine separation actuation circuit includes a third one of said plurality of switches actuable to an open position a predetermined time after operation of said second one of said plurality of switches thereby to permanently render ineffective said mine separation actuation circuit.
 4. An electrical control system according to claim 1 wherein a fourth one of said plurality of electrical switches is operable a predetermined time after ignition of said electroresponsive programmer means for interrupting the connection between said electroresponsive programmer means and said first electrical energy source.
 5. An electrical control system according to claim 1 wherein said electroresponsive programmer means includes an elongate explosive power train having a controlled burning rate and a plurality of piston means each being disposed at spaced positions along the length of said train and movable to effect operation of respective ones of said plurality of switches as the burning of said train reaches the respective position of each of said piston means. 